Low current heaterless hollow cathode neutralizer for plasma propulsion-Development overview

Hollow cathodes serve as electron sources for the operation of electric thrusters aboard spacecraft. Conventionally, hollow cathodes utilize a heating element to raise the temperature of the electron emitting material embedded in the cathode. To simplify cathode design and operation, in recent years, heaterless cathode technology has been under development in various facilities around the world. This paper overviews the development of a low current heaterless hollow cathode, designed and produced by Rafael, and denoted the ARC-1A. The ARC-1A generates a discharge current of 0.3-1.2 A and is ignited using breakdown voltages below 400 V. Each of the development phases is elaborated upon. These phases included activities such as a technology study, the development of manufacturing processes, the study of failure modes, and performance characterization and culminated with two primary tests-a 5000 h endurance test and a 3500 cold ignition cycles test. In its current state of development, the ARC-1A proves suitable for a wide range of low power electric thrusters and was successfully coupled with two different Hall effect thrusters in a wide range of low discharge current levels (0.5-1.1 A).